My amp is labeled 12AU7-6SN7-ECC82 on two tube sockets,
I would have bet that all 3 tubes had same pin out ...
JJ 6SN7 data sheet shows plate to cathodes are on pins 1,2 and 5,6
Schematic to my amp says plate to cathodes are at 5,6 and 2,3
Pulled up another 6SN7 and holy moly, it shows plate to cathodes 1,3 and 6,8
There is zero consistency. Mark from Blueglow has a 6SN7 diagram matching my setup...
Just what in the heck is going on ?
I would have bet that all 3 tubes had same pin out ...
JJ 6SN7 data sheet shows plate to cathodes are on pins 1,2 and 5,6
Schematic to my amp says plate to cathodes are at 5,6 and 2,3
Pulled up another 6SN7 and holy moly, it shows plate to cathodes 1,3 and 6,8
There is zero consistency. Mark from Blueglow has a 6SN7 diagram matching my setup...
Just what in the heck is going on ?
The JJ data sheet I pulled up shows plate/cathode at 2/3 and 5/6, consistent with your amp and the RCA and GE data sheets. The diagrams can be difficult to read without magnifying the images. All have 8-pin octal bases.
12AU7 / ECC82 is a different tube, using a 9-pin base of smaller diameter - they are not plug-compatible.
12AU7 / ECC82 is a different tube, using a 9-pin base of smaller diameter - they are not plug-compatible.
How on Earth can an amp, ANY amp, have that label near sockets?
6SN7 has EIGHT FAT pins in an OCTAL base, 12AU7 has NINE SKINNY legs in a NOVAL base.
I would worry about that way more than about mere pín assignment, don´t you think?
6SN7 has EIGHT FAT pins in an OCTAL base, 12AU7 has NINE SKINNY legs in a NOVAL base.
I would worry about that way more than about mere pín assignment, don´t you think?
And 12AU7 <> 6SN7. The former has shorter plates than the later. 6FQ7 is closer to 6SN7, created for multivibrators and for the synchroguide circuit. Some 6FQ7 have a shield piece wired to pin #9.
So, there is a saying.. you learn from your mistakes... Made 2 and compounded both!
Amp is labeled 6N8P 6SN7 6H8C !!!!
I looked up 6sn7, read the "modern equivalent is....." BUT that didn't mean what I though !!!
I'm sure you can fill in the blanks from there....
2nd mistake, DON'T measure voltage drop across a resistor with a low impedance auto ranging DMM!!
I knew that 2nd one and forgot it.. A wisp of magic smoke on the previous resistor reminded me .....
So, by the time I get done making mistakes, I should be a genius 😎
Amp is labeled 6N8P 6SN7 6H8C !!!!
I looked up 6sn7, read the "modern equivalent is....." BUT that didn't mean what I though !!!
I'm sure you can fill in the blanks from there....
2nd mistake, DON'T measure voltage drop across a resistor with a low impedance auto ranging DMM!!
I knew that 2nd one and forgot it.. A wisp of magic smoke on the previous resistor reminded me .....
So, by the time I get done making mistakes, I should be a genius 😎
I am guessing this is not a mistake and you have a Chinese amp? There are routinely adapters for 12AU7 in 6SN7 socket and vice versa for cheap on auction and sales sites. As long as it's 6V filament supply and the transformers can supply the additional heater current (6SN7 in a 9 pin socket), it shouldn't be a problem (with the right socket adapter).
I made a mistake... see the post just above yours... Looking into the 6SN7 I read somewhere that the modern equivalent was the 12AU7 and took that to mean it was a direct replacement..